Corvette Fuel Systems - Fueling The Fire

Planning & Setting Up A Fuel System For Your Corvette

These are the major components you'll need to assemble a reliable fuel delivery system for an uber-performance Corvette: Inline fuel pump with bypass (more below), high capacity fuel pressure regulator and a pair of filters (pre-filter and after-filter).

Flash back over three and a half decades. It was a gorgeous late spring day. Temperatures were in the mid to high eighties. The t-tops were off. The big block was running at full song. Seemingly in an instant, the gas pedal went spongy. The rat motor stumbled a wee bit, and then simply quit. We popped the hood in an effort to diagnose the problem. As it turned out the combination of a tight engine compartment, big compression (the factory LS6 was fitted with 12.25:1 pistons and converted to LS7 internal specifications) and big tube headers was simply too much for the fuel delivery system - big stock fuel pump and all. The fuel was percolating in the fuel bowls as well as in the fuel lines. The recurring dilemma was eventually overcome with almost every band-aid fix known to man. But it was never wholly resolved. Aside from boiling the fuel, there likely wasn't sufficient volume to satisfy a thirsty, big horsepower big block.

When it comes to fuel delivery systems, there's no question that big is pretty much the operative word. Proof is the honking fuel pump you'll typically find nestled beside the fuel cell in a NHRA Pro Stock racecar. The trouble is if you have a modified street-driven Corvette--fuel injected or carbureted--then you'll find yourself at a fuel delivery crossroad. You see, with a big cubic inch engine on board, or one with a serious power adder or two (blower, turbo, nitrous or even a combination of the three), there's a definite need for plenty of fuel. On the other hand, those big monster pumps that feed a Pro Stock drag car don't particularly like to run for extended periods of time such as in a street driven car. They weren't designed for that purpose. And heat becomes an issue (this is really critical if the pump configuration doesn't incorporate some form of return or by-pass system - deadheading pumps build heat in a big hurry). The foremost reason is there is nothing to cool the big electric motors used in these pumps.

So what electric pumps are designed for the purpose? You just have to take a look at a modern fuel injected Corvette for some insight. In those applications, the pumps are engineered so that the fuel runs through them. As a result, the fuel supply actually cools the pump as it operates. That means the pump in question can run pretty much wide open for as long as necessary (and as long as there is fuel in the tank).

Does this mean you're stuck with one of those little itsy-bitsy in-tank pumps that are found on most late model Corvettes? Not at all. Several companies offer big in-line fuel pumps that are engineered so that fuel runs through them (for extended operation). Case-in-point is the MagnaFuel 625 pump shown in the accompanying photos. This particular pump offers a number of features you should look for when shopping for a pump:

Aside from the continuous duty capability, this pump is self-priming. That means you don't have to fret about pump mounting. In fact, it is possible to install it vertically or horizontally (mount bracket included). Another bonus is the pump size. It's physically rather small, measuring just under 7.50-inches in length (not counting the fittings or the by-pass). Taking the mount bracket into consideration, the pump measures just under 3.75-inches in height while the body diameter is 3.00-inches.

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Corvette Fuel Systems - Fueling The Fire

These are the major components you'll need to assemble a reliable fuel delivery system for an uber-performance Corvette: Inline fuel pump with bypass (more below), high capacity fuel pressure regulator and a pair of filters (pre-filter and after-filter).

This is the MagnaFuel pump we're using in a home-brewed 572. This pump can support an EFI or carbureted engine that produces 1,500 HP. For the modified normally aspirated application (and most others), this pretty much exceeds the engine requirements. This pump can deliver anywhere from 20-120 PSI in use. When it was designed, MagnaFuel took other considerations into account. One of the most important was a steady fuel delivery curve from idle to full throttle. Another was quick response coupled with maximum cooling. Because of these design factors, reliability isn't a problem. The body of the pump is machined from 6061-T6 aircraft grade aluminum alloy. Internally, the pump uses a proprietary gear drive, flow-through configuration, allowing for big pressure capability, reliability and quiet operation in one package.

In terms of overall size, the in-line pump measures just under 9.250-inches long (with the by-pass assembly attached) by 3.00-inches across. With the mount bracket attached, the pump is 3.75-inches tall. These dimensions do not take into account the inlet and outlet fittings. The pump is massive in comparison to something like a common Bosch EFI booster pump, but it is definitely compact when lined up against one of today's Pro Stock racecar pumps.